Sitting East, plan the defense to four spades on partner’s lead of the heart seven. When you have made up your mind, look at the full deal to see why playing the heart ace at trick one is a bad idea.

It might be hard to explain to partner why you violated the rule of third hand high if your partner has led a singleton or if declarer has a bare king. Equally, if declarer has the doubleton king, you will score one trick sooner or later, whatever you do. However, if declarer has three cards in the suit, you need to put in the 10 now; if you take the ace and return the suit, you have lost your entry to cash the third round.

Declarer will take the second heart and drive out the trump ace, then can lead a diamond to his 10 to establish a diamond discard for his heart loser. However, if you put in the heart 10 at the first trick, declarer is immediately dead in the water.

Admittedly there are two positions where playing the ace wins, and only one where playing the 10 does, but that does not take into account the significance of partner’s spot-card lead. If the seven is only consistent with a doubleton or singleton, the odds change dramatically in favor of playing the 10 at trick one.

(Incidentally, this sort of deal is further justification for leading low and not MUD from three small in partner’s suit, unless you have supported him.)

ANSWER: Some people would argue that with an opening bid you should always get into the auction. Indeed, facing an unpassed partner, I can see the merits of doubling here. But with so many of your values in spades and with partner having passed, it might be too risky to act. Your side might miss a partscore, but surely never a game.